1. Field of the Invention
This invention relates to the field of tools for cutting plastic pipes and more particularly to the field of hand-held tools for cutting hard plastic pipes wherein the tools have accompanying clamping arrangements to firmly grip the pipe and aid in maintaining the proper alignment of the tool""s cutting portion.
2. Discussion of the Background
Plastic pipe cutters are widely available for cutting pipes of relatively hard plastics such as polyvinylchloride (PVC) and acrylonitrile butadiene styrene (ABS). Such pipes are commonly used in many applications to drain water and waste and to vent such systems. They are also used to contain electrical wiring. In cutting such pipes, it is desirable to have an accompanying clamping arrangement to firmly grip the pipe and additionally guide and maintain the cutting portion in the proper alignment with the pipe for a clean, straight cut.
In this regard and with manual or hand-held cutting tools that consist only of a scissor-like arrangement of pivoted blades, it is often very difficult to maintain the proper alignment with the pipe. In particular and as the handles of the tool are squeezed together and moved about the pipe, there is a tendency for the tool to rock or cock to one side out of a perpendicular alignment with the axis of the pipe. The result can be that the blades form a cutting path that spirals along the pipe and/or the final cut is not straight. With many such tools, the edges of the final cut are often irregular and raised and need to be sanded or otherwise smoothed to properly be received in a fitting. Adding a clamping arrangement to accompany the cutting portion of the tool to keep the cutting portion from rocking or cocking to one side greatly improves the quality of the cut. However, most such clamping arrangements are quite elaborate and somewhat difficult and time consuming to set up and use. They are for the most part impractical to use in the field to quickly and efficiently cut a hard plastic pipe, particularly pipes that are partially buried or otherwise in cramped quarters.
With this and other problems in mind, the present invention was developed. In it, a combined clamping and cutting tool is provided that can be effectively and efficiently used to cut plastic pipes. Both the clamping and cutting portions of the tool are manually operated and are mounted together as a unit for ease of use and storage.
This invention involves a cutting tool for plastic pipes. The tool has a clamping portion and a cutting portion operably connected together. The cutting portion includes a pair of elongated members pivotally mounted to each other with each elongated member having a handle section and a cutting section. Each cutting section has a main body with a pair of cutting wheels mounted to it. The cutting wheels are preferably mounted for rotation about axes substantially parallel to the pivotal axis of the elongated members.
The clamping portion includes at least three members with the first and second members pivotally mounted to each other and the second and third members pivotally mounted to each other. The first member has a handle section and clamping section and the second member also includes a clamping section. The third member has a handle section which is mounted to the second member for pivotal movement. Each clamping section has a pair of spaced-apart, parallel legs that firmly and slidably receive the cutting sections of the cutting portion therebetween. Interlocking tracks are also provided to maintain the clamping and cutting portions together during use and to provide an interaction between the two portions to aid in opening them to receive the pipe.
In operation, the handles of the clamping and cutting portions of the assembled tool can be manually manipulated to open the respective clamping and cutting sections to receive the pipe. In doing so, there is an interaction between the interlocking tracks on the two portions to aid in their opening. Once on the pipe with the clamping portion firmly gripping it, the handles of the cutting portion can be squeezed and reciprocated along an arc about the pipe to progressively advance the cutting wheels into and through the pipe to make a cut. The cutting wheels preferably have a radius section on them which bevels or rounds the outer edge of the pipe for a smooth, clean cut that can be easily received and sealed in a fitting.